Relay device and air conditioning system

ABSTRACT

A relay device communicably connects an upper-level air conditioning system and a lower-level air conditioning system that use different protocols. An upper-side communicator is connected to a first bus, and transmits and receives communication packets to and from the upper-level air conditioning system. A lower-side communicator is connected to an outdoor device that is a master device, and transmits and receives communication commands to and from the lower-level air conditioning system. An association information memory stores association information obtained by associating an address in the upper-level air conditioning system allocated to each device in the lower-level air conditioning system with identification information on each device in the lower-level air conditioning system. A processor performs a mutual conversion on the communication packets and the communication commands based on the association information stored in the association information memory.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 15/118,946filed on Aug. 15, 2016, which is a U.S. national stage application ofInternational Patent Application No. PCT/JP2014/065453 filed on Jun. 11,2014, the disclosure of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a relay device that relays systemsconstructed by different protocols, and an air conditioning system thatincludes multiple systems constructed by different protocols.

BACKGROUND ART

Conventionally, systems that manage (monitor, control) an airconditioner and a lighting device and the like are placed in a buildingor a house. Examples of such systems are (i) a large-scale airconditioning system (upper-level system) that includes a central controldevice, several outdoor devices, and several tens of indoor devices, and(ii) an intermediate and small scale air conditioning system(lower-level system) that includes an outdoor device and several indoordevices.

Such upper-level systems and lower-level systems often have differencesnot only in the scale but also in the protocol. Hence, it has been knowna method of connecting both systems through a relay device provided witha protocol conversion function.

For example, Patent Literature 1 discloses an invention of connecting anair conditioner using a different protocol to a central managementsystem including a central management device that manages multipleequipment instruments through a relay device (equipment instrumentadaptor).

In addition, Patent Literature 2 discloses an invention of connecting afield bus (lower-level system in which outdoor devices and indoordevices are connected via local bus) using a different protocol to anupper-level bus (bus of upper-level system) of a network system througha relay device (converter).

CITATION LIST Patent Literature

Patent Literature 1: Japanese Patent No. 4179297

Patent Literature 2: Unexamined Japanese Patent Application KokaiPublication No. 2004-301430

SUMMARY OF INVENTION Technical Problem

According to the invention disclosed in Patent Literature 1, however,one relay device is necessary per connection of one air conditioner tothe central management system. Hence, when a large number of airconditioners are connected to a large-scale central management system torealize the large-scale central management system, relay devices whosenumber is the same as the number of the air conditioners are necessary.This makes the system configuration complicated, and increases thesystem costs.

In addition, according to the invention disclosed in Patent Literature2, the upper-level bus and the local bus are connected through the relaydevice. Hence, when, the lower-level system adopts a master-slave methodof controlling, from the outdoor device that is a master device, theindoor device that is a slave device, a problem of an increase in thecommunication bandwidth of the local bus is caused. For example, whenthe indoor device in the lower-level system is controlled by theupper-level system, control commands are initially transmitted from theupper-level system to the indoor device in the lower-level system, butin the lower-level system, once the control commands are transferred tothe outdoor device from the indoor device (from slave device to masterdevice), and then control commands are eventually transmitted from theoutdoor device to the indoor device (from master device to slave device)in the lower-level system. Eventually, the communication bandwidth ofthe local bus increases. In general, since the lower-level system isinexpensive in comparison with the upper-level system, when thecommunication bandwidth excessively increases, a reduction in servicesuch as a communication difficulty may occur.

The present disclosure has been made to solve the aforementionedproblems, and an objective of the present disclosure is to provide arelay device and an air conditioning system that are capable ofperforming appropriate communication between systems constructed withdifferent protocols.

Solution to Problem

In order to achieve the above objective, a relay device according to thepresent disclosure is configured to connect an upper-level system and alower-level system, and to relay communication between the upper-levelsystem and the lower-level system, the upper-level system including aplurality of devices connected via a first bus and performingcommunication using an address allocated to each of the devices, thelower-level system including a plurality of devices connected via asecond bus and performing communication in the master-slave method withany one of the devices being as a master device and other devices beingas slave devices, and the relay device comprising:

an upper-side communicator configured to be connected to the first bus,and to transmit and receive communication packets to and from theupper-level system;

a lower-side communicator configured to be connected to the masterdevice, and to transmit and receive communication commands to and fromthe lower-level system;

an association information memory configured to store associationinformation obtained by associating the address in the upper-levelsystem allocated to each of the plurality of devices in the lower-levelsystem with identification information on each of the plurality ofdevices in the lower-level system; and

a processor configured to perform a mutual conversion on thecommunication packets and the communication commands based on theassociation information stored in the association information memory.

Advantageous Effects of Invention

According to the relay device of the present disclosure, the upper-sidecommunicator is connected to the first bus of the upper-level system,and the lower-side communicator is connected to the master device in thelower-level system. In addition, the processor performs a mutualconversion on the communication packets in the upper-level system andthe communication commands in the lower-level system based on theassociation information stored in the association information memory.This enables appropriate communication between systems constructed bydifferent protocols.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating an example of an entireconfiguration of an air conditioning system based on Embodiment 1 of thepresent disclosure;

FIG. 2 is a schematic diagram illustrating an example of associationinformation stored in an association information memory in Embodiment 1;

FIG. 3 is a sequence diagram for explaining a data flow from a centralcontrol device to an indoor device in Embodiment 1;

FIG. 4 is a sequence diagram for explaining a data flow from the indoordevice to the central control device in Embodiment 1;

FIG. 5 is a block diagram illustrating an example of an entireconfiguration of an air conditioning system based on a modified exampleof Embodiment 1 of the present disclosure;

FIG. 6 is a block diagram illustrating an example of an entireconfiguration of an air conditioning system based on Embodiment 2 of thepresent disclosure;

FIG. 7 is a sequence diagram for explaining a data flow from a centralcontrol device to an indoor device in Embodiment 2;

FIG. 8 is a sequence diagram for explaining a data flow from the indoordevice to the central control device in Embodiment 2;

FIG. 9 is a block diagram illustrating an example of an entireconfiguration of an air conditioning system based on Embodiment 3 of thepresent disclosure;

FIG. 10 is a schematic diagram illustrating an example of associationinformation stored in an association information memory in Embodiment 3;and

FIG. 11 is a sequence diagram for explaining a data flow from a centralcontrol device to an indoor device in Embodiment 3.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure will be explained below in detailwith reference to the figures. Note that the same or equivalent portionthroughout the figures will be denoted by the same reference numeral.The following explanation will be given for a specific example in whichthe present disclosure is applied to an air conditioning system, but aswill be explained later, the present disclosure is also applicable toother systems. That is, the embodiments that will be explained below arefor explanation only, and are not intended to limit the scope of thepresent disclosure. Hence, a person skilled in the art could carry outan embodiment in which each or all of elements are replaced withequivalents, and such embodiment should be within the scope of thepresent disclosure.

(Embodiment 1)

FIG. 1 is a block diagram illustrating an example of an entireconfiguration of an air conditioning system based on Embodiment 1 of thepresent disclosure. As illustrated in the figure, the air conditioningsystem has an upper-level air conditioning system 1 and a lower-levelair conditioning system 2 that are connected with each other through arelay device 200. The upper-level air conditioning system 1 isconstructed by, for example, a large-scale air conditioning system. Onthe other hand, the lower-level air conditioning system 2 is constructedby, for example, an intermediate and small scale air conditioningsystem.

The upper-level air conditioning system 1 and the lower-level airconditioning system 2 are constructed by different protocols. Forexample, in the upper-level air conditioning system 1, mutualcommunication is conducted based on communication packets flowing over afirst bus 10 using the address set for each device as will be explainedlater. On the other hand, in the lower-level air conditioning system 2,communication is conducted in the master-slave method using theidentification information (device ID) of each device as will beexplained later. For example, in the lower-level air conditioning system2, a control instruction and a data acquisition are performed between amaster device and a slave device via a second bus 20 based oncommunication commands (more specifically, internal communicationcommands explained later).

(Configuration of Upper-level Air Conditioning System 1 in Embodiment 1)

As illustrated in FIG. 1, the upper-level air conditioning system 1 hasa central control device 100, an outdoor device 110, and an indoordevice 120 that are connected via the first bus 10. In this FIG. 1, anexample of simplified upper-level air conditioning system 1 isillustrated, but in practice, several tens of outdoor devices 110, andseveral tens of indoor devices 120 may be connected to the first bus 10.In addition, the first bus 10 is also connected to the relay device 200.

The central control device 100 performs a central control on theoperation of the outdoor device 110 and that of the indoor device 120.In addition, the central control device 100 is also capable ofcontrolling the operation of an outdoor device 300 in the lower-levelair conditioning system 2 and that of an indoor device 400 (400 a-400 c)therein through the relay device 200.

The outdoor device 110 includes, for example, a compressor and aheat-source-end heat exchanger, and is connected to the indoor device120 via piping. The outdoor device 110 circulates a cooling mediumbetween the outdoor device 110 and the indoor device 120 via thispiping. Note that the outdoor device 110 controls the outdoor device 110in accordance with communication packets whose destination is theaddress of the outdoor device 110 transmitted over the first bus 10.

The indoor device 120 includes, for example, an expansion valve and aload-end heat exchanger, and is connected to the outdoor device 110 viapiping. The indoor device 120 causes the load-end heat exchanger toevaporate or condense the cooling medium, thereby performing an airconditioning on a space subjected to air conditioning. Note that theindoor device 120 controls the indoor device 120 in accordance withcommunication packets whose destination is the address of the indoordevice 120 transmitted over the first bus 10.

(Configuration of Relay Device 200 in Embodiment 1)

The relay device 200 includes an upper-side communicator 210, anassociation information memory 220, a processor 230, and a lower-sidecommunicator 240.

The upper-side communicator 210 includes, for example, an interface thatcan be connected to the first bus 10, and performs communication witheach device in the upper-level air conditioning system 1. The upper-sidecommunicator 210 performs communication using information such as anaddress stored (registered) in the association information memory 220 asexplained later. More specifically, when the destination ofcommunication packets over the first bus 10 is the registered address(that is, address of any one of the devices in the lower-level airconditioning system 2) in the association information memory 220 theupper-side communicator 210 receives the communication packets, andsupplies the received packets to the processor 230 (communication packetreception process). In addition, the upper-side communicator 210transmits, over the first bus 10, serial communication packets (morespecifically, communication packets converted by the processor 230 fromserial communication commands transmitted from the lower-level airconditioning system 2) created by the processor 230 (communicationpacket transmission process).

The association information memory 220 includes, for example, a databaseand the like, and stores, for each device in the lower-level airconditioning system 2, association information indicating theassociation relationship between the address and the device ID. As anexample, the association information memory 220 stores associationinformation 221 illustrated in FIG. 2. This association information 221defines, for the address allocated to each device in the lower-level airconditioning system 2, the device ID, the device name and the like, toidentify each device. Note that the address is an available value overthe first bus 10 of the upper-level air conditioning system 1. Further,the value not redundant with those of the outdoor device 110 and indoordevice 120 explained above is allocated to the address.

Returning to FIG. 1, the processor 230 includes, for example, a CentralProcessing Unit (CPU), a Read Only Memory (ROM), and a Random AccessMemory (RAM), reads a program stored in the ROM or the like to the RAM,and causes the CPU to execute the read program, thereby executingvarious processes. More specifically, the processor 230 analyzes (i) thecommunication packets received by the upper-side communicator 210 fromthe upper-level air conditioning system 1, and (ii) the serialcommunication commands received by the lower-side communicator 240 fromthe lower-level air conditioning system 2 (analysis process). Inaddition, the processor 230 refers to the association information 221stored in the association information memory 220 to create communicationpackets (convert serial communication commands to communicationpackets), and instructs the upper-side communicator 210 to transmit thecreated packets (communication packet creation process). Still further,the processor 230 likewise refers to the association information 221 tocreate serial communication commands (convert communication packets toserial communication commands), and instructs the lower-sidecommunicator 240 to transmit the created commands (serial communicationcommand creation process).

The lower-side communicator 240 includes, for example, an interface (asan example, serial communication interface) that can be connected withthe outdoor device 300 in the lower-level air conditioning system 2, andperforms communication with the outdoor device 300 and the indoor device400 (400 a-400 c) via the outdoor device 300. More specifically, thelower-side communicator 240 receives serial communication commandstransmitted from the outdoor device 300, and supplies the receivedcommands to the processor 230 (serial communication command receptionprocess). In addition, the lower-side communicator 240 transmits serialcommunication commands created by the processor 230 to the outdoordevice 300 (serial communication command transmission process).

(Configuration of Lower-level Air Conditioning System 2 in Embodiment 1)

The lower-level air conditioning system 2 includes the outdoor device300 and the indoor device 400 (400 a-400 c) that are connected with eachother via the second bus 20. In addition, the outdoor device 300 isconnected to the above mentioned relay device 200 (lower-sidecommunicator 240) via, for example, a serial communication interface.Note that the configuration of each device in the lower-level airconditioning system 2 is merely an example, and the number of outdoordevice 300 and that of indoor device 400 can be modified as appropriate.When there are multiple outdoor devices 300 in the lower-level airconditioning system 2, only one outdoor device 300 becomes a masterdevice as explained later, and the other outdoor devices 300 becomeslave devices as explained later like the indoor device 400.

In the lower-level air conditioning system 2 illustrated in FIG. 1, theoutdoor device 300 is a master device, and the indoor device 400 (400a-400 c) is a slave device, thereby performing communication in themaster-slave method. That is, the indoor device 400 that is the slavedevice determines the operation of the indoor device 400 in accordancewith control commands (more specifically, internal communicationcommands) from the outdoor device 300 that is the master device. Inaddition, the outdoor device 300 controls the indoor device 400 andperforms setting for the indoor device 400. Still further, the outdoordevice 300 obtains response data and the like from the indoor device400. The device ID is given to each device in the lower-level airconditioning system 2, and the device ID is used during thecommunication in the master-slave method. As an example, the device IDthat is “ABC001” is given to the indoor device 400, and the device IDsthat are “ABC002”, “ABC003”, and “ABC004” are respectively given to theindoor devices 400 a, 400 b, and 400 c.

(Configuration of Outdoor Device 300 in Lower-level Air ConditioningSystem 2 in Embodiment 1)

The outdoor device 300 includes a serial communicator 310, a processor320, and an internal communicator 330. Note that the outdoor device 300(i) includes, in addition to those components, for example, acompressor, a heat-source-end heat exchanger and the like, to achieveoriginal functions of the device, and (ii) is connected to the indoordevice 400 (400 a-400 c) via piping. The outdoor device 300 circulatesthe cooling medium between the outdoor device 300 and the indoor device400 via the piping.

The serial communicator 310 includes, for example, an interface (as anexample, serial communication interface) that can be connected to theabove lower-side communicator 240, and performs communication with therelay device 200. More specifically, the serial communicator 310receives serial communication commands transmitted from the relay device200, and supplies the received commands to the processor 320 (serialcommunication command reception process). In addition, the serialcommunicator 310 transmits, to the relay device 200, the serialcommunication commands created by the processor 320 (serialcommunication command transmission process).

The processor 320 includes, for example, a CPU, a ROM and a RAM, readsthe program stored in the ROM or the like to the RAM, and causes the CPUto execute the read program, thereby executing various processes. Morespecifically, the processor 320 analyzes (i) the serial communicationcommands received by the serial communicator 310 from the relay device200, and (ii) the internal communication commands received by theinternal communicator 330 from the indoor device 400 (400 a-400 c)(analysis process). In addition, the processor 320 creates serialcommunication commands, and instructs the serial communicator 310 totransmit the created commands (serial communication command creationprocess). Still further, the processor 320 creates internalcommunication commands, and instructs the internal communicator 330 totransmit the created commands (internal communication command creationprocess).

The internal communicator 330 includes, for example, an interface thatcan be connected to the second bus 20, and performs communication withthe indoor device 400 (400 a-400 c) in the lower-level air conditioningsystem 2 in the master-slave method. More specifically, the internalcommunicator 330 receives the internal communication commandstransmitted from the indoor device 400, and supplies the receivedcommands to the processor 320 (internal communication command receptionprocess). In addition, the internal communicator 330 transmits, theinternal communication commands created by the processor 320, to theindoor device 400 (internal communication command transmission process).

(Indoor Device 400 of Lower-level Air Conditioning System 2 inEmbodiment 1)

The indoor device 400 (400 a-400 c) analyzes the internal communicationcommands transmitted from the outdoor device 300 and controls the indoordevice 400 (control process). In addition, the indoor device 400notifies the outdoor device 300 of response data, such as the status ofthe indoor device 400 and the setting thereof (response process). Stillfurther, the indoor device 400 analyzes the internal communicationcommands transmitted from devices other than the outdoor device 300 (forexample, remote controller) and changes the setting of the indoor device400. At this time, the indoor device 400 changes the setting, but doesnot change the operation of the indoor device 400 until receiving, fromthe outdoor device 300, the internal communication commands containingthe details of a control change. Note that the indoor device 400 (i)includes, in addition to those components, for example, an expansionvalve and a load-end heat exchanger and the like, to achieve theoriginal functions of the device, and (ii) is connected to the outdoordevice 300 via the piping. The indoor device 400 causes the load-endheat exchanger to evaporate or condense the cooling medium, therebyperforming an air conditioning on a space subjected to the airconditioning.

(Operation of Entire Air Conditioning System in Embodiment 1)

Operations of the entire air conditioning system will be explained belowwith reference to FIGS. 3 and 4. FIG. 3 is a sequence diagramillustrating a data flow when the indoor device 400 a is controlled bythe central control device 100. That is, in a sequence diagram of FIG.3, a data flow from the upper-level air conditioning system 1 to thelower-level air conditioning system 2 through the relay device 200 willbe explained. In addition, FIG. 4 is a sequence diagram illustrating adata flow when the indoor device 400 a notifies the central controldevice 100 of response data. That is, in a sequence diagram of FIG. 4, adata flow from the lower-level air conditioning system 2 to theupper-level air conditioning system 1 through the relay device 200 willbe explained.

First, with reference to FIG. 3, an explanation will be given for a dataflow when the indoor device 400 a is controlled by the central controldevice 100.

First, the central control device 100 transmits communication packets toa destination that is the indoor device 400 a (sequence sq11). That is,the central control device 100 transmits, over the first bus 10,communication packets whose destination is an address “192.168.xxx.xx2”.Note that the communication packets contain the address of the centralcontrol device 100, i.e., the transmitter.

Since communication packets transmitted over the first bus 10 aredirected to the device in the lower-level air conditioning system 2, theupper-side communicator 210 of the relay device 200 receives thecommunication packets (sequence sq12). That is, when determining thatthe address “192.168.xxx.xx2” which is the destination of thecommunication packets matches one of the addresses contained in theassociation information 221 illustrated in FIG. 2 above, the upper-sidecommunicator 210 executes the communication packet reception process toreceive the communication packets, and supplies the received packets tothe processor 230.

The processor 230 analyzes the communication packets received by theupper-side communicator 210, and creates serial communication commands(sequence sq13). That is, first, the processor 230 executes the analysisprocess to analyze the communication packets received by the upper-sidecommunicator 210. Next, the processor 230 executes the serialcommunication command creation process and, with reference to theassociation information 221, converts the communication packets toserial communication commands. At this time, the processor 230 creates,in accordance with the association information 221 illustrated in FIG.2, the serial communication commands whose destination is the device ID“ABC002” that corresponds to the address “192.168.xxx.xx2”. Note thatthe transmission originator is unchanged which is the address of thecentral control device 100. Next, the processor 230 instructs thelower-side communicator 240 to transmit the created serial communicationcommands.

The lower-side communicator 240 transmits the serial communicationcommands created by the processor 230 to the outdoor device 300(sequence sq14). That is, the lower-side communicator 240 executes theserial communication command transmission process to transmit, to theoutdoor device 300, the serial communication commands whose destinationis the device ID “ABC002”.

The serial communicator 310 of the outdoor device 300 receives theserial communication commands transmitted from the relay device 200(sequence sq15). That is, the serial communicator 310 executes theserial communication command reception process to receive the serialcommunication commands whose destination is the device ID “ABC002”, andsupplies the received commands to the processor 320.

The processor 320 analyzes the serial communication commands received bythe serial communicator 310, and creates the internal communicationcommands (sequence sq16). That is, first, the processor 320 executes theanalysis process to analyze the serial communication commands that arereceived by the serial communicator 310 from the relay device 200. Next,the processor 320 executes the internal communication command creationprocess to create the internal communication commands for controllingthe indoor device 400 a denoted with the device ID “ABC002”, andinstructs the internal communicator 330 to transmit the createdcommands.

The internal communicator 330 transmits the internal communicationcommands created by the processor 320 to the indoor device 400 a(sequence sq17). That is, the internal communicator 330 transmits theinternal communication commands toward the indoor device 400 a that isthe slave device.

The indoor device 400 a receives the internal communication commandstransmitted from the outdoor device 300 (sequence sq18).

The indoor device 400 a analyzes the received internal communicationcommands, and controls the indoor device 400 a (sequence sq19). That is,the indoor device 400 a executes the control process to analyze theinternal communication commands received from the outdoor device 300,and to control the indoor device 400 a in accordance with the internalcommunication commands.

Next, with reference to FIG. 4, an explanation will be given for a dataflow when the indoor device 400 a notifies the central control device100 of response data. Note that, as an example, the indoor device 400 anotifies the central control device of the response data in response torequest data from the central control device 100. However, the flow ofthe request data from the central control device 100 to the indoordevice 400 a is the same as the flow illustrated in FIG. 3. Hence, theexplanation thereof will be omitted. The explanation will be given belowfirst for the process of the indoor device 400 a after the request datais received.

The indoor device 400 a that has received the request data createsresponse data in accordance with such request (sequence sq21). That is,the indoor device 400 a creates internal communication commands thatcontain response data. Note that the received request data contains, forexample, the address of the central control device 100 as the address ofthe transmitter. Hence, the indoor device 400 a creates the internalcommunication commands in which the address of the central controldevice 100 is set to be the destination and the device ID “ABC002” ofthe indoor device 400 a is set to be the transmission originator.

The indoor device 400 a transmits the created internal communicationcommands to the outdoor device 300 (sequence sq22).

The internal communicator 330 of the outdoor device 300 receives theinternal communication commands transmitted from the indoor device 400 a(sequence sq23). That is, the internal communicator 330 executes theinternal communication command reception process to receive the internalcommunication commands transmitted from the indoor device 400 a, andsupplies the received commands to the processor 320.

The processor 320 analyzes the internal communication commands receivedby the internal communicator 330, and creates serial communicationcommands (sequence sq24). That is, first, the processor 320 executes theanalysis process to analyze the internal communication commands that arereceived by the internal communicator 330 from the indoor device 400 a.Next, the processor 320 executes the serial communication commandcreation process to create the serial communication commands, andinstructs the serial communicator 310 to transmit the created commands.

The serial communicator 310 transmits the serial communication commandscreated by the processor 320 to the relay device 200 (sequence sq25).That is, the serial communicator 310 executes the serial communicationcommand transmission process to transmit, to the relay device 200, theserial communication commands created by the processor 320.

The lower-side communicator 240 of the relay device 200 receives theserial communication commands transmitted from the outdoor device 300(sequence sq26). That is, the lower-side communicator 240 executes theserial communication command reception process to receive the serialcommunication commands transmitted from the outdoor device 300, andsupplies the received commands to the processor 230.

The processor 230 analyzes the serial communication commands received bythe lower-side communicator 240, and creates communication packets(sequence sq27). That is, the processor 230 first executes the analysisprocess to analyze the serial communication commands received by thelower-side communicator 240. Next, the processor 230 executes thecommunication packet creation process, and converts the serialcommunication commands to the communication packets with reference tothe association information 221. At this time, the processor 230creates, in accordance with the association information 221 illustratedin FIG. 2, the communication packets in which as the transmissionoriginator, the address “192.168.xxx.xx2” corresponding to the device ID“ABC002” is set. Note that the destination is unchanged which is theaddress of the central control device 100. Next, the processor 230instructs the upper-side communicator 210 to transmit the createdcommunication packets.

The upper-side communicator 210 transmits the communication packetsdirected to the central control device 100 (sequence sq28). That is, theupper-side communicator 210 executes the communication packettransmission process to transmit, over the first bus 10, thecommunication packets in which a destination is set to be the address ofthe central control device 100.

Since the communication packets transmitted over the first bus 10 aredirected to the central control device 100, the central control device100 receives the communication packets (sequence sq29). That is, thecentral control device 100 receives the communication packets thatrespond to the request, and obtains the response data from the indoordevice 400 a.

(Advantageous Effects of Embodiment 1)

As explained above, in accordance with the air conditioning system inEmbodiment 1 of the present disclosure, the lower-level air conditioningsystem 2 that includes the outdoor device 300 and the multiple indoordevices 400 is connectable to the upper-level air conditioning system 1by use of the single relay device 200. Hence, an air conditioningsystem, in which communication is possible between systems that areconstructed by different protocols, can be realized at low costs.

In addition, the relay device 200 stores, in the association informationmemory 220, the association information 221 obtained by associating theaddress which can be used in the upper-level air conditioning system 1(address allocated to each device in lower-level air conditioning system2) with the device ID of each device in the lower-level air conditioningsystem 2. Hence, when the device in the lower-level air conditioningsystem 2 is controlled by the device in the upper-level air conditioningsystem 1, the relay device 200 converts the communication packets to thecommunication commands (more specifically, serial communicationcommands) by use of the association information 221, and transmits thecommands to the lower-level air conditioning system 2. Hence, in theupper-level air conditioning system 1, a process of identifying whetherthe device to be controlled is the device in the upper-level airconditioning system 1 or the device in the lower-level air conditioningsystem 2 is unnecessary, and the device in the lower-level airconditioning system 2 can be controlled and monitored like the device inthe upper-level air conditioning system 1.

In addition, in accordance with conventional configurations in whicheach device in the lower-level air conditioning system 2 is connected tothe relay device 200, even if communication is performed between thedevices in the lower-level air conditioning system 2, the communicationis performed through the internal region of the upper-level airconditioning system 1. Accordingly, a problem of increase in thecommunication bandwidth of the upper-level air conditioning system 1 iscaused. By employing the configuration of Embodiment 1, however, thecommunication between the devices in the lower-level air conditioningsystem 2 is performed within the lower-level air conditioning system 2.This leads to an advantageous effect that communication bandwidth of theupper-level air conditioning system 1 is not increased.

Still further, in Embodiment 1, the indoor device 400 (400 a-400 c) inthe lower-level air conditioning system 2 does not require an interfacewith the relay device 200, and thus the configuration of the indoordevice 400 of the lower-level air conditioning system 2 can be designedwithout a particular consideration of the connection with theupper-level air conditioning system 1.

Yet still further, in accordance with conventional configurations inwhich the relay device 200 directly transmits control commands to thedevice to be controlled in the lower-level air conditioning system 2,when the device in the lower-level air conditioning system 2 iscontrolled by the upper-level air conditioning system 1, there aredisadvantages such as an increased response time. That is, althoughcontrol commands are initially transmitted from the upper-level airconditioning system 1 to the indoor device 400 in the lower-level airconditioning system 2, in the lower-level air conditioning system 2,once the control commands are transferred (control details are notified)from the indoor device 400 to the outdoor device 300, and then thecontrol commands are eventually transmitted to the indoor device 400from the outdoor device 300. Consequently, the response time becomeslong, and the communication bandwidth of the second bus 20 increases.According to Embodiment 1, however, an operation configuration isemployed in which the outdoor device 300 receives, from the upper-levelair conditioning system 1, the communication commands directed to theindoor device 400 in the lower-level air conditioning system 2 (morespecifically, serial communication commands through relay device 200)and transmits the communication commands (more specifically, internalcommunication commands) to the indoor device 400. This leads toadvantageous effects such as a reduced response time.

Moreover, in accordance with conventional configurations in which therelay device 200 directly transmits control commands to the indoordevice 400 which is the device to be controlled in the lower-level airconditioning system 2, there is a case where both the upper-level airconditioning system 1 and the outdoor device 300 in the lower-level airconditioning system 2 individually control the indoor device 400 in thelower-level air conditioning system 2. Thus, an inconsistency in controlof the indoor device 400 may occur. According to Embodiment 1, however,an operation configuration is employed in which the outdoor device 300receives, from the upper-level air conditioning system 1, thecommunication commands directed to the indoor device 400 in thelower-level air conditioning system 2 and transmits the communicationcommands to the indoor device 400. This leads to advantageous effectsthat no inconsistency in control of the indoor device 400 is causedbetween the upper-level air conditioning system 1 and the outdoor device300 in the lower-level air conditioning system 2.

As explained above, according to the air conditioning system inEmbodiment 1 of the present disclosure, appropriate communication can beperformed between systems constructed by different protocols withoutincreasing system costs and without unnecessarily increasing thecommunication bandwidth of the lower-level air conditioning system 2.

(Modified Example in Embodiment 1)

The Embodiment 1 of the present disclosure has been explained above, butthe specific configuration is not limited to Embodiment 1. Designchanges, and the like, without departing from the scope of the presentdisclosure can be made.

According to Embodiment 1, when the data on the indoor device 400 in thelower-level air conditioning system 2 is obtained at the upper-level airconditioning system 1, the request data is transmitted to the indoordevice 400 in the lower-level air conditioning system 2. When, however,the outdoor device 300 has data of the indoor device 400 (requesteddata), the outdoor device 300 may create response data and reply withouttransmitting the request data to the indoor device 400. By employingsuch an operation, advantageous effects of reducing the response timeand the communication bandwidth of the second bus 20 is achieved.

In the above Embodiment 1, the explanation has been given for a case inwhich the relay device 200 and the outdoor device 300 in the lower-levelair conditioning system 2 are connected via serial communication.However, the communication between the relay device 200 and the outdoordevice 300 may be speeded up faster than, for example, the second bus 20connecting the outdoor device 300 and the indoor device 400. Accordingto this configuration, when the indoor device 400 in the lower-level airconditioning system 2 is controlled by the upper-level air conditioningsystem 1, an advantageous effect of reducing a control time (responsetime until control is reflected) is achieved.

In addition, in the above Embodiment 1, the explanation has been givenfor a case in which the communication between the relay device 200 andthe outdoor device 300 in the lower-level air conditioning system 2, andthe communication between the outdoor device 300 and the indoor device400 are conducted through different communication interfaces. However,the communication between the relay device 200 and the outdoor device300, and the communication between the outdoor device 300 and the indoordevice 400 may share a common communication interface. Morespecifically, as illustrated in FIG. 5, the communication between arelay device 500 and the outdoor device 300 is also performed via thesecond bus 20.

That is, the configuration of the relay device 500 in the airconditioning system illustrated in FIG. 5 is different from that of therelay device 200 illustrated in FIG. 1. In addition, the relay device500 and the lower-level air conditioning system 2 are connected via thesecond bus 20. Note that in the following explanation, the commoncomponent and the like to that of Embodiment 1 will be denoted by thesame reference numeral. That is, the configuration of the upper-levelair conditioning system 1 and that of the lower-level air conditioningsystem 2 are the same as those in FIG. 1.

The relay device 500 includes the upper-side communicator 210, theassociation information memory 220, a processor 530, and an internalcommunicator 540. The configuration of the upper-side communicator 210and that of the association information memory 220 are the same as thoseof the relay device 200 in FIG. 1.

The processor 530 analyzes (i) the communication packets that arereceived by the upper-side communicator 210 from the upper-level airconditioning system 1, and (ii) the internal communication commands thatare received by the internal communicator 540 from the lower-level airconditioning system 2 (analysis process). In addition, the processor 530refers to the association information 221 stored in the associationinformation memory 220, creates communication packets (converts internalcommunication commands to communication packets), and instructs theupper-side communicator 210 to transmit the created packets(communication packet creation process). Still further, the processor530 likewise refers to the association information 221, creates internalcommunication commands (converts communication packets to internalcommunication commands), and instructs the internal communicator 540 totransmit the created commands (internal communication command creationprocess).

The internal communicator 540 includes, for example, an interfaceconnectable with the second bus 20, and performs communication with theoutdoor device 300 and the indoor device 400 (400 a-400 c) via theoutdoor device 300. More specifically, the internal communicator 540receives the internal communication commands transmitted from theoutdoor device 300, and supplies the received commands to the processor530 (internal communication command reception process). In addition, theinternal communicator 540 transmits the internal communication commandscreated by the processor 530 to the outdoor device 300 (internalcommunication command transmission process).

The relay device 500 employing such configuration executes, whenreceiving, from the upper-level air conditioning system 1, thecommunication commands directed to the indoor device 400 in thelower-level air conditioning system 2 (more specifically, convertedinternal communication commands), a process of transmitting the receivedcommunication commands to the outdoor device 300. This enables anaccomplishment of the advantageous effect similar to that of Embodiment1.

(Embodiment 2)

The relay device 200 and the outdoor device 300 in the lower-level airconditioning system 2 according to the above Embodiment 1 employ theconfigurations illustrated in FIG. 1, but may alternatively employconfigurations illustrated in FIG. 6. The air conditioning system ofEmbodiment 2 of the present disclosure, illustrated in FIG. 6, differsfrom the outdoor device 300 and the lower-level air conditioning system2 of Embodiment 1 in that the above configuration of the relay device200 is incorporated in an outdoor device 600 to omit the relay device200. That is, in accordance with the air conditioning system inEmbodiment 2, the upper-level air conditioning system 1 and thelower-level air conditioning system 3 are configured to be connectedwith each other. In the following explanation, the component and thelike, common to that in Embodiment 1 will be denoted by the samereference numeral. That is, the upper-level air conditioning system 1employs the same configuration as the configuration in FIG. 1.

(Configuration of Lower-level Air Conditioning System 3 in Embodiment 2)

A lower-level air conditioning system 3 illustrated in FIG. 6 includesthe outdoor device 600 and the indoor device 400 (400 a-400 c) that areconnected with each other via the second bus 20. In addition, theoutdoor device 600 is connected with the upper-level air conditioningsystem 1 via the first bus 10. In the lower-level air conditioningsystem 3 also, the outdoor device 600 that is the master devicecommunicates with the indoor device 400 that is the slave device in themaster-slave method.

(Configuration of Outdoor Device 600 in Lower-level Air ConditioningSystem in Embodiment 2)

The outdoor device 600 includes the upper-side communicator 210, theassociation information memory 220, a processor 630, and the internalcommunicator 330. Note that the outdoor device 600 (i) includes, inaddition to those components, for example, a compressor and aheat-source-end heat exchanger and the like to achieve the originalfunction of the device, and (ii) is connected to the indoor device 400(400 a-400 c) via piping. The outdoor device 600 circulates the coolingmedium between the outdoor device 600 and the indoor device 400 throughthis piping.

The configuration of the upper-side communicator 210 and that of theassociation information memory 220 are the same as those of the abovementioned relay device 200 illustrated in FIG. 1. In addition, theconfiguration of the internal communicator 330 is the same as that ofthe above mentioned outdoor device 300 in FIG. 1.

The processor 630 includes, for example, a CPU, a ROM and a RAM, reads aprogram stored in the ROM or the like to the RAM, and causes the CPU toexecute the read program, thereby executing various processes. Morespecifically, the processor 630 analyzes (i) the communication packetsthat are received by the upper-side communicator 210 from theupper-level air conditioning system 1, and (ii) the internalcommunication commands that are received by the internal communicator330 from the indoor device 400 (400 a-400 c) (analysis process). Inaddition, the processor 630 refers to the association information 221stored in the association information memory 220, creates communicationpackets (converts internal communication commands to communicationpackets), and instructs the upper-side communicator 210 to transmit thecreated packets (communication packet creation process). Still further,the processor 630 likewise refers to the association information 221,creates internal communication commands (converts communication packetsto internal communication commands), and instructs the internalcommunicator 330 to transmit the created commands (internalcommunication command creation process).

(Operations of Entire Air Conditioning System in Embodiment 2)

An explanation will be given below for operations of the entire airconditioning system with reference to FIGS. 7 and 8. FIG. 7 is asequence diagram illustrating a data flow when the indoor device 400 ais controlled by the central control device 100. That is, in thesequence diagram of FIG. 7, a data flow from the upper-level airconditioning system 1 to the lower-level air conditioning system 3 willbe explained. In addition, FIG. 8 is a sequence diagram illustrating adata flow when the indoor device 400 a notifies the central controldevice 100 of response data. That is, in the sequence diagram of FIG. 8,a data flow from the lower-level air conditioning system 3 to theupper-level air conditioning system 1 will be explained. Note that inthe following explanation, the process details common to that ofEmbodiment 1 will be denoted by the same reference numeral.

First, with reference to FIG. 7, a data flow when the indoor device 400a is controlled by the central control device 100 will be explained.

First, the central control device 100 transmits communication packetsdirected to the indoor device 400 a (sequence sq11). That is, thecentral control device 100 transmits, over the first bus 10,communication packets whose destination is the address of the indoordevice 400 a.

Since the communication packets transmitted over the first bus 10 aredirected to the device (indoor device 400 a) in the lower-level airconditioning system 3, the upper-side communicator 210 of the outdoordevice 600 receives such communication packets (sequence sq32).

The processor 630 analyzes the communication packets received by theupper-side communicator 210, and creates the internal communicationcommands (sequence sq33). That is, the processor 630 first executes theanalysis process to analyze the communication packets received by theupper-side communicator 210. Next, the processor 630 executes theinternal communication command creation process to convert thecommunication packets to the internal communication commands withreference to the association information 221.

The internal communicator 330 transmits the internal communicationcommands created by the processor 630 to the indoor device 400 a(sequence sq34).

The indoor device 400 a receives the internal communication commandstransmitted from the outdoor device 600 (sequence sq18).

The indoor device 400 a analyzes the received internal communicationcommands (sequence sq19), and controls the indoor device 400 a. That is,the indoor device 400 a executes the control process to analyze theinternal communication commands received from the outdoor device 600,and to control the indoor device 400 a in accordance with these internalcommunication commands.

Next, with reference to FIG. 8, an explanation will be given for a dataflow when the indoor device 400 a notifies the central control device100 of response data. As an example, the indoor device 400 a notifiesthe central control device 100 of the response data in response to therequest data from the central control device 100. The flow of requestdata from the central control device 100 to the indoor device 400 a isthe same as that illustrated in FIG. 7. Hence, the explanation will beomitted. An explanation will be given below first for the process by theindoor device 400 a after receiving the request data.

The indoor device 400 a that has received the request data creates theresponse data in accordance with the request (sequence sq21). That is,the indoor device 400 a creates the internal communication commandscontaining the response data.

The indoor device 400 a transmits the created internal communicationcommands to the outdoor device 600 (sequence sq22).

The internal communicator 330 of the outdoor device 600 receives theinternal communication commands transmitted from the indoor device 400 a(sequence sq43).

The processor 630 analyzes the internal communication commands receivedby the internal communicator 330, and creates the communication packets(sequence sq44). That is, the processor 630 first executes the analysisprocess to analyze the internal communication commands received by theinternal communicator 330. Next, the processor 630 executes thecommunication packet creation process to convert the internalcommunication commands to the communication packets with reference tothe association information 221.

The upper-side communicator 210 transmits the communication packetsdirected to the central control device 100 (sequence sq45). That is, theupper-side communicator 210 executes the communication packettransmission process to transmit, over the first bus 10, thecommunication packets whose destination is the address of the centralcontrol device 100.

The central control device 100 receives the communication packetstransmitted over the first bus 10 (sequence sq29) since suchcommunication packets are directed to the central control device 100.That is, the central control device 100 receives the communicationpackets responding to the request, and obtains the response data fromthe indoor device 400 a.

(Advantageous Effects of Embodiment 2)

As explained above, according to the air conditioning system inEmbodiment 2 of the present disclosure, the lower-level air conditioningsystem 3 that includes the outdoor device 600 and the multiple indoordevices 400 is connectable to the upper-level air conditioning system 1without using the relay device 200 and the like. Hence, an airconditioning system, in which communication is possible between systemsconstructed by different protocols, can be realized at low costs.

In addition, the outdoor device 600 stores, in the associationinformation memory 220, the association information 221 obtained byassociating an address that can be used in the upper-level airconditioning system 1 (address allocated to each device in lower-levelair conditioning system 3) with the device ID of each device in thelower-level air conditioning system 3. Hence, when the device in thelower-level air conditioning system 3 is controlled by the device in theupper-level air conditioning system 1, the outdoor device 600 convertsthe communication packets to the communication commands (morespecifically, internal communication commands) using this associationinformation 221, and transmits the commands to the indoor device 400.Hence, in the upper-level air conditioning system 1, a process ofidentifying whether the device to be controlled is the device in theupper-level air conditioning system 1 or the device in the lower-levelair conditioning system 3 is unnecessary, and like the device in theupper-level air conditioning system 1, the device in the lower-level airconditioning system 3 can be controlled and monitored.

Still further, in accordance with conventional configurations in whicheach device in the lower-level air conditioning system 3 is connected tothe relay device 200, even if communication is performed between thedevices in the lower-level air conditioning system 3, the communicationis performed through the internal region of the upper-level airconditioning system 1. Thus, a problem of increase in the communicationbandwidth of the upper-level air conditioning system 1 is caused. Byemploying the configuration of Embodiment 2, however, the communicationbetween the devices in the lower-level air conditioning system 3 isperformed within the lower-level air conditioning system 3. This leadsto an advantageous effect that the communication bandwidth of theupper-level air conditioning system 1 is not increased.

Yet still further, in Embodiment 2, the indoor device 400 (400 a-400 c)in the lower-level air conditioning system 3 does not require aninterface with the relay device 200 (relay device 200 itself iseliminated), and thus the configuration of the indoor device 400 in thelower-level air conditioning system 3 can be designed without aparticular consideration of the connection with the upper-level airconditioning system 1.

Moreover, in accordance with conventional configurations in which therelay device 200 directly transmits control commands to the device to becontrolled in the lower-level air conditioning system 3, when the devicein the lower-level air conditioning system 3 is controlled by theupper-level air conditioning system 1, there are disadvantages such asan increased response time. That is, although control commands areinitially transmitted from the upper-level air conditioning system 1 tothe indoor device 400 in the lower-level air conditioning system 3, oncethe control commands are transferred (control details are notified) fromthe indoor device 400 to the outdoor device 600, and then the controlcommands are eventually transmitted to the indoor device 400 from theoutdoor device 600 in the lower-level air conditioning system 3.Consequently, the response time becomes long, and the communicationbandwidth of the second bus 20 increases. According to Embodiment 2,however, an operation configuration is employed in which the outdoordevice 600 (i) receives , from the upper-level air conditioning system1, the communication packets directed to the indoor device 400 in thelower-level air conditioning system 3 and (ii) transmits thecommunication commands (more specifically, internal communicationcommands) to the indoor device 400. Accordingly, there are advantageouseffects such as a reduced response time.

In addition, in accordance with conventional configurations in which therelay device 200 directly transmits control commands to the indoordevice 400 which is the device to be controlled in the lower-level airconditioning system 3, the upper-level air conditioning system 1 and theoutdoor device 600 in the lower-level air conditioning system 3individually control the indoor device 400 in the lower-level airconditioning system 3. Thus, this may probably cause an inconsistency incontrolling the indoor device 400. According to Embodiment 2, however,an operation configuration is employed in which the outdoor device 600(i) receives, from the upper-level air conditioning system 1, thecommunication packets directed to the indoor device 400 in thelower-level air conditioning system 3 and (ii) transmits thecommunication commands to the indoor device 400. This leads toadvantageous effects that the upper-level air conditioning system 1 andthe outdoor device 600 in the lower-level air conditioning system 3 donot cause inconsistency in controlling the indoor device 400 .

As explained above, in accordance with the air conditioning system inEmbodiment 2 of the present disclosure, appropriate communication can becarried out between systems constructed by different protocols withoutincreasing system costs and without unnecessarily increasing thecommunication bandwidth of the lower-level air conditioning system 3.

(Embodiment 3)

The air conditioning system in the above Embodiment 1 employs the abovementioned configuration illustrated in FIG. 1, but may also employ theother configuration illustrated in FIG. 9. An air conditioning system inEmbodiment 3 of the present disclosure illustrated in FIG. 9, differsfrom that in Embodiment 1 in that in Embodiment 3, the multiplelower-level air conditioning systems 2 (lower-level air conditioningsystems 2 a and 2 b) that have different channels are connected to theupper-level air conditioning system 1 through a relay device 700. Thatis, according to the air conditioning system in Embodiment 3, the relaydevice 700 switches the connection to each lower-level air conditioningsystem 2, and is communicable with the device in the lower-level airconditioning system 2. Note that in the following explanation, thecomponent common to that of Embodiment 1 will be denoted by the samereference numeral. That is, the configuration of the upper-level airconditioning system 1 and that of each lower-level air conditioningsystem 2 are the same as those in FIG. 1. In addition, the explanationwill be given by regarding that the lower-level air conditioning system2 a is “channel A”, and the lower-level air conditioning system 2 b is“channel B”.

(Configuration of Relay Device 700 in Embodiment 3)

The relay device 700 includes the upper-side communicator 210, anassociation information memory 720, a processor 730, and a lower-sidecommunicator 740. Note that the configuration of the upper-sidecommunicator 210 is the same as that of the relay device 200 in FIG. 1.

The association information memory 720 includes, for example, a databaseand the like, and stores, for each device in the lower-level airconditioning system 2 of each channel, association informationindicating the association relationship among the address, the channel,and the device ID. As an example, the association information memory 720stores association information 721 illustrated in FIG. 10. Thisassociation information 721 defines, for the address allocated to eachdevice in each lower-level air conditioning system 2, a value indicatingthe channel (value indicating “channel A” or “channel B”), the deviceID, the device name and the like, for identifying each device. Note thatthe address is a value that can be used over the first bus 10 of theupper-level air conditioning system 1. The value not redundant withthose of the outdoor device 110 and indoor device 120 are allocated tothe address.

Returning to FIG. 9, the processor 730 includes, for example, a CPU, aROM, a RAM and the like, reads the program stored in the ROM or the liketo the RAM, and causes the CPU to execute the read program, therebyexecuting various processes. Specifically, the processor 730 analyzes(i) the communication packets that are received by the upper-sidecommunicator 210 from the upper-level air conditioning system 1, and(ii) the serial communication commands that are received by thelower-side communicator 740 from any one of the lower-level airconditioning system 2 (analysis process). In addition, the processor 730refers to the association information 721 stored in the associationinformation memory 720, creates the communication packets (convertsserial communication commands to communication packets), and instructsthe upper-side communicator 210 to transmit the created packets(communication packet creation process). Still further, the processor730 likewise refers to the association information 721, creates theserial communication commands (converts communication packets to serialcommunication commands), specifies the channel, and instructs thelower-side communicator 740 to transmit the created commands (serialcommunication command creation process). Note that, as will be explainedlater, when the lower-side communicator 740 (connection switcher 741)itself switches the connection destination, the specification of thechannel may be omitted.

The lower-side communicator 740 includes, for example, the connectionswitcher 741, and an interface (as an example, serial communicationinterface) that can be connected to the outdoor device 300 in eachlower-level air conditioning system 2 through the connection switcher741.

The connection switcher 741 includes, for example, a connection changingswitch having electric components such as transistors. The connectionswitcher 741 switches the connection destination to either an outdoordevice 300 a in the lower-level air conditioning system 2 a or anoutdoor device 300 b in the lower-level air conditioning system 2 b inaccordance with the channel specified by the processor 730. For example,when the “channel A” is specified, the connection switcher 741 switchesthe connection destination to the outdoor device 300 a, andalternatively when the “channel B” is specified, the connection switcher741 switches the connection destination to the outdoor device 300 b. Theconnection switcher 741 maintains the connection until (i) the serialcommunication commands are transmitted to the outdoor device 300, i.e.,the connection destination and (ii) a response from the outdoor device300 is obtained. Instead of switching the connection destination inaccordance with the specification by the processor 730, the connectionswitcher 741 may itself analyze the serial communication commands (referto the above mentioned association information 721 and the like), andswitch the connection to the outdoor device 300 of the channel inaccordance with the device ID of the destination.

The lower-side communicator 740 including the connection switcher 741performs communication with the outdoor device 300 which is theconnection destination in the lower-level air conditioning system 2, andthe indoor device 400 through this outdoor device 300. Morespecifically, the lower-side communicator 740 receives the serialcommunication commands transmitted from the outdoor device 300 which isthe connection destination, and supplies the received commands to theprocessor 730 (serial communication command reception process). Inaddition, the lower-side communicator 740 transmits the serialcommunication commands created by the processor 730 to the outdoordevice 300 which is the connection destination (serial communicationcommand transmission process).

(Operation of Entire Air Conditioning System in Embodiment 3)

An explanation will be given below for the operation of the entire airconditioning system with reference to FIG. 11. FIG. 11 is a sequencediagram illustrating a data flow when an indoor device 400 d in thelower-level air conditioning system 2 b is controlled by the centralcontrol device 100. That is, in the sequence diagram of FIG. 11, a dataflow from the upper-level air conditioning system 1 to any one of thelower-level air conditioning system 2 (in this case, lower-level airconditioning system 2 b) through the relay device 700 will be explained.Note that in the following explanation, the process detail common tothat of Embodiment 1 will be denoted by the same reference numeral.

First, the central control device 100 transmits the communicationpackets directed to the indoor device 400 d (sequence sq11). That is,the central control device 100 transmits, over the first bus 10, thecommunication packets whose destination is the address“192.168.xxx.xx6”.

Since the communication packets transmitted over the first bus 10 aredirected to the device in the lower-level air conditioning system 2(more specifically, lower-level air conditioning system 2 b), theupper-side communicator 210 in the relay device 700 receives suchcommunication packets (sequence sq12). That is, the upper-sidecommunicator 210 executes, when determining that the address“192.168.xxx.xx6” which is the destination of the communication packetsmatches one of the addresses stored in the association information 721illustrated in FIG. 10 above, the communication packet reception processto receive the communication packets, and supplies the received packetsto the processor 730.

The processor 730 analyzes the communication packets received by theupper-side communicator 210, and creates serial communication commands(sequence sq13). That is, first, the processor 730 executes the analysisprocess to analyze the communication packets received by the upper-sidecommunicator 210. Next, the processor 730 executes the serialcommunication command creation process to convert the communicationpackets to serial communication commands with reference to theassociation information 721. At this time, the processor 730 creates, inaccordance with the association information 721 illustrated in FIG. 10,the serial communication commands whose destination is the device ID“BCD002” corresponding to the address “192.168.xxx.xx6”. Next, theprocessor 730 specifies the “channel B”, and instructs the lower-sidecommunicator 740 to transmit the created serial communication commands.Note that when the connection switcher 741 itself switches theconnection destination, the specification of the channel may be omitted.

The lower-side communicator 740 switches the connection destination(sequence sq51). That is, the connection switcher 741 switches theconnection destination to either the outdoor device 300 a or the outdoordevice 300 b in accordance with the channel specified by the processor730. In this case, since the “channel B” is specified, the connectionswitcher 741 switches the connection destination to the outdoor device300 b. Instead of switching the connection destination in accordancewith the specification by the processor 730, the connection switcher 741may itself analyze the serial communication commands (for example, withreference to the above association information 721), and switch theconnection to the outdoor device 300 b of the “channel B” in accordancewith the device ID “BCD002” which is a destination.

The lower-side communicator 740 transmits the serial communicationcommands created by the processor 730 to the outdoor device 300 b(sequence sq14). That is, the lower-side communicator 740 executes theserial communication command transmission process to transmit, to theoutdoor device 300 b which is the connection destination, the serialcommunication commands whose destination is the device ID “BCD002”.

The serial communicator 310 of the outdoor device 300 b receives theserial communication commands transmitted from the relay device 700(sequence sq15). That is, the serial communicator 310 executes theserial communication command reception process to receive the serialcommunication commands whose destination is the device ID “BCD002”, andsupplies the received commands to the processor 320.

The processor 320 analyzes the serial communication commands received bythe serial communicator 310, and creates the internal communicationcommands (sequence sq16). That is, first, the processor 320 executes theanalysis process to analyze the serial communication commands that arereceived by the serial communicator 310 from the relay device 700. Next,the processor 320 executes the internal communication command creationprocess to create the internal communication commands for controllingthe indoor device 400 d whose device ID is “BCD002”, and instructs theinternal communicator 330 to transmit the created commands.

The internal communicator 330 transmits the internal communicationcommands created by the processor 320 to the indoor device 400 d(sequence sq17). That is, the internal communicator 330 transmits theinternal communication commands to the indoor device 400 d that is theslave device.

The indoor device 400 d receives the internal communication commandstransmitted from the outdoor device 300 b (sequence sq18).

The indoor device 400 d analyzes the received internal communicationcommands, and controls the indoor device 400 d (sequence sq19). That is,the indoor device 400 d executes the control process to analyze theinternal communication commands received from the outdoor device 300 b,and to control the indoor device 400 d in accordance with the internalcommunication commands.

In addition, the data flow when the indoor device 400 d in thelower-level air conditioning system 2 b notifies the central controldevice 100 of response data is the same as that illustrated in FIG. 4since the connection switcher 741 maintains the connection.

(Advantageous Effects of Embodiment 3)

As explained above, according to the air conditioning system inEmbodiment 3 of the present disclosure, the lower-level air conditioningsystems 2 (lower-level air conditioning system 2 including the outdoordevice 300 and the multiple indoor devices 400) that have a plurality ofchannels are connectable to the upper-level air conditioning system 1through the single relay device 700. Hence, an air conditioning system,in which communication is possible between systems constructed bydifferent protocols, can be realized at low costs.

In addition, the relay device 700 stores, in the association informationmemory 720, the association information 721 obtained by associating theaddress usable in the upper-level air conditioning system 1 (addressallocated to each device in each lower-level air conditioning system 2)with the device ID of each device in each lower-level air conditioningsystem 2. Hence, when the device in any one of the lower-level airconditioning systems 2 is controlled by the device in the upper-levelair conditioning system 1, the relay device 700 converts thecommunication packets to the communication commands (more specifically,serial communication commands) using this association information 721,and transmits the commands to the target lower-level air conditioningsystem 2. Hence, in the upper-level air conditioning system 1, a processof identifying whether the device to be controlled is the device in theupper-level air conditioning system 1 or the device in the lower-levelair conditioning system 2 of any channel is unnecessary, and the devicein each lower-level air conditioning system 2 can be controlled andmonitored like the device in the upper-level air conditioning system 1.

In addition, in accordance with conventional configurations in whicheach device in the lower-level air conditioning system 2 is connected tothe relay device 700, even if communication is performed between thedevices in the lower-level air conditioning system 2, the communicationis performed through the internal region of the upper-level airconditioning system 1. Thus, a problem of increase in the communicationbandwidth of the upper-level air conditioning system 1 is caused. Byemploying the configuration of Embodiment 3, however, the communicationbetween the devices of the lower-level air conditioning system 2 in thesame channel is performed within each lower-level air conditioningsystem 2. This leads to an advantageous effect that the communicationbandwidth of the upper-level air conditioning system 1 does notincrease.

Still further, in Embodiment 3, the indoor device 400 (400 a-400 c) ineach lower-level air conditioning system 2 does not require an interfacewith the relay device 700. Thus, the configuration of the indoor device400 in each lower-level air conditioning system 2 can be designedwithout a particular consideration of the connection with theupper-level air conditioning system 1.

Yet still further, in accordance with conventional configurations inwhich the relay device 700 directly transmits control commands to thedevice to be controlled in the lower-level air conditioning system 2,when the device in the lower-level air conditioning system 2 iscontrolled by the upper-level air conditioning system 1, there aredisadvantages such as the increased response time. That is, althoughcontrol commands are initially transmitted from the upper-level airconditioning system 1 to the indoor device 400 in the target lower-levelair conditioning system 2, in the lower-level air conditioning system 2,once the control commands are transferred (control details are notified)from the indoor device 400 to the outdoor device 300, and then thecontrol commands are eventually transmitted to the indoor device 400from the outdoor device 300. This causes the increased response time andthe increased communication bandwidth of the second bus 20. According toEmbodiment 3, however, an operation configuration is employed in whichthe outdoor device 300 receives, from the upper-level air conditioningsystem 1, the communication commands (more specifically, serialcommunication commands through relay device 700) directed to the indoordevice 400 which is a device to be controlled in the lower-level airconditioning system 2 and transmits the communication commands (morespecifically, internal communication commands) to the indoor device 400.This leads to advantageous effects such as a reduced response time.

Moreover, in accordance with conventional configurations in which therelay device 700 directly transmits control commands to the indoordevice 400 that is a device to be controlled in the lower-level airconditioning system 2, there is a case where the upper-level airconditioning system 1 and the outdoor device 300 in the lower-level airconditioning system 2 individually control the indoor device 400 in thelower-level air conditioning system 2. This causes the possibility thatan inconsistency in controlling the indoor device 400 occurs. Accordingto Embodiment 3, however, an operation configuration is employed inwhich the outdoor device 300 receives, from the upper-level airconditioning system 1, the communication commands directed to the indoordevice 400 which is the connection destination in the lower-level airconditioning system 2 and transmits the communication commands to theindoor device 400. This leads to advantageous effects that theupper-level air conditioning system 1 and the outdoor device 300 whichis the connection destination in the lower-level air conditioning system2 do not cause inconsistency in controlling the indoor device 400.

As explained above, according to the air conditioning system inEmbodiment 3 of the present disclosure, appropriate communication can becarried out between systems constructed by different protocols withoutincreasing system costs and without unnecessarily increasing thecommunication bandwidth of the lower-level air conditioning system 2.

(Modified Example in Embodiment 3)

Although Embodiment 3 of the present disclosure has been explained, thespecific configuration is not limited to Embodiment 3, and designchanges without departing from the scope of the present disclosure canbe made.

In Embodiment 3, when data on the indoor device 400 which is the controldestination in the lower-level air conditioning system 2 is to beobtained by the upper-level air conditioning system 1, the request datais transmitted to the indoor device 400 in the lower-level airconditioning system 2. However, in the same channel, when the outdoordevice 300 holds data (requested data) of the indoor device 400, theoutdoor device 300 may create the response data and reply withouttransmitting the request data to the indoor device 400. By employingsuch operations, there are advantageous effects such as the reducedresponse time and the reduced communication bandwidth of the second bus20.

In Embodiment 3, the explanation has been given for a case in which therelay device 700 and the outdoor device 300 in each lower-level airconditioning system 2 are connected via serial communication. However,the communication between the relay device 700 and the outdoor device300 may be speeded up faster than, for example, the second bus 20connecting the outdoor device 300 to the indoor device 400. By employingthis configuration, when the indoor device 400 in any one of lower-levelair conditioning systems 2 is controlled by the upper-level airconditioning system 1, there is an advantageous effect that a controltime (response time until control is reflected) is further reduced.

In Embodiment 3 above, the explanations have been given for a case wherethe lower-side communicator 740 (connection switcher 741) of the relaydevice 700 electrically switches the communication line using theconnection changing switch that includes electric components such astransistors in order to have connection with the outdoor device 300 inthe multiple lower-level air conditioning systems 2 that have differentchannels. However, the connection between the relay device 700 and eachlower-level air conditioning system 2 may be accomplished by otherschemes. For example, communication between the relay device 700 andeach lower-level air conditioning system 2 (outdoor device 300) isperformed via the second bus 20. That is, the second buses 20 in each ofthe lower-level air conditioning systems 2 are connected, and furtherthe second bus 20 is connected to the relay device 700. At this time,like the relay device 500 illustrated in FIG. 5 above, the relay device700 includes, instead of the lower-side communicator 740, the internalcommunicator 540. Next, the relay device 700 (internal communicator 540)transmits the internal communication commands over the second bus 20.Since the internal communication commands contain the device ID of thedestination device, the corresponding device receives and processes theinternal communication commands. Note that the internal communicationcommands may further contain information indicating the channel. In thiscase, in the corresponding channel, the device corresponding to thedevice ID receives and processes the internal communication commands.Those operations make unnecessary, for the relay device 700, to switchthe connection destination depending on the destination of the createdinternal communication commands. Accordingly, the process load of therelay device 700 can be reduced.

In Embodiment 3 above, the explanation has been given for a case inwhich every time communication is necessary, the lower-side communicator740 (connection switcher 741) of the relay device 700 switches theconnection destination. However, communication may be performed whilethe lower-side communicator 740 of the relay device 700 sequentiallyswitching the connection to the outdoor device 300 in each lower-levelair conditioning system 2 at each predetermined time. For example, therelay device 700 transmits the serial communication commands to theoutdoor device 300 in each lower-level air conditioning system 2 at aconstant cycle.

In this case, when the lower-side communicator 740 (connection switcher741) of the relay device 700 employs a configuration in which thecommunication line is electrically switched using the connectionchanging switch that includes electric components such as transistors,it becomes unnecessary to switch the connection changing switchdepending on the destination of the serial communication commands to betransmitted. Hence, an overhead time at which the relay device 700transmits the serial communication commands (time necessary forswitching the connection changing switch) can be reduced, and thecommunication efficiency in serial communication can be improved.

Even if communication between the relay device 700 and each lower-levelair conditioning system 2 (outdoor device 300) is performed via thesecond bus 20, the relay device 700 may transmit the internalcommunication commands to the outdoor device 300 in each lower-level airconditioning system 2 at constant cycle. For example, the timings of therelay device 700 and the outdoor device 300 of each lower-level airconditioning system 2 are synchronized, and the outdoor device 300 a andthe outdoor device 300 b individually receive the internal communicationcommands transmitted from the relay device 700 within the timings setfor each outdoor device. Hence, for the internal communication commandstransmitted from the relay device 700, information for identifying towhich lower-level air conditioning systems 2 of which channel, thedestination device belongs becomes unnecessary. Accordingly, thecommunication efficiency in internal communication can be improved.

(Other Embodiments)

In the above embodiments, the upper-level air conditioning system 1 hasbeen explained as an example of an upper-level system, and thelower-level air conditioning systems 2 and 3 have been explained asexamples of a lower-level system. However, the present disclosure islikewise applicable to other systems. For example, the presentdisclosure is applicable, as appropriate, to a lighting system that hasan upper-level lighting system as an upper-level system and alower-level lighting system as a lower-level system connected with eachother through a relay device and the like.

In the above embodiments, the explanation has been given for a case inwhich a dedicated relay device 200 and the like, is used. However, if aprogram that defines the operations of such dedicated relay device 200is applied to a conventional personal computer and an informationterminal device and the like, such a personal computer and the like canfunction as the relay device 200 and the like of the present disclosure.

In addition, how to distribute such a program is optional, and forexample, the program may be stored in a non-transitory computer-readablerecording medium, such as a Compact Disc Read-Only Memory (CD-ROM), aDigital Versatile Disc (DVD), a Magneto Optical disc (MO), or a memorycard for the distribution, or may be distributed via a communicationnetwork such as Internet.

The foregoing describes some example embodiments for explanatorypurposes. Although the foregoing discussion has presented specificembodiments, persons skilled in the art will recognize that changes maybe made in form and detail without departing from the broader spirit andscope of the invention. Accordingly, the specification and drawings areto be regarded in an illustrative rather than a restrictive sense. Thisdetailed description, therefore, is not to be taken in a limiting sense,and the scope of the invention is defined only by the included claims,along with the full range of equivalents to which such claims areentitled.

INDUSTRIAL APPLICABILITY

The present disclosure is suitably applicable to a relay device thatrelays systems constructed by different protocols, and an airconditioning system including multiple systems constructed by differentprotocols.

REFERENCE SIGNS LIST

1 Upper-level air conditioning system

2, 3 Lower-level air conditioning system

10 First bus

20 Second bus

100 Central control device

200, 500, 700 Relay device

110, 300, 600 Outdoor device

120, 400 Indoor device

210 Upper-side communicator

220, 720 Association information memory

230, 320, 530, 630, 730 Processor

240, 740 Lower-side communicator

310 Serial communicator

330, 540 Internal communicator

741 Connection switcher

The invention claimed is:
 1. An air conditioning system comprising anupper-level air conditioning system and a lower-level air conditioningsystem connected with each other through a relay device, the upper-levelair conditioning system including at least one central control device,at least one outdoor device, and at least one indoor device that areconnected via a first bus and performing communication using an addressallocated to each device, the lower-level air conditioning systemincluding at least one outdoor device and at least one indoor devicethat are connected via a second bus and performing communication in amaster-slave method with any one of the outdoor devices being as amaster device and other devices being as slave devices, the relay devicecomprising: an upper-side communicator configured to be connected to thefirst bus, and to transmit and receive communication packets to and fromthe upper-level air conditioning system; a lower-side communicatorconfigured to be connected to the master device, and to transmit andreceive communication commands to and from the lower-level airconditioning system; an association information memory configured tostore association information obtained by associating the address in theupper-level air conditioning system allocated to each device in thelower-level air conditioning system with identification information oneach device in the lower-level air conditioning system; and a processorconfigured to perform a mutual conversion on the communication packetsand the communication commands based on the association informationstored in the association information memory.
 2. An air conditioningsystem comprising an upper-level air conditioning system and alower-level air conditioning system, the upper-level air conditioningsystem including at least one central control device, at least oneoutdoor device, and at least one indoor device that are connected via afirst bus and performing communication using an address allocated toeach device, the lower-level air conditioning system including at leastone outdoor device and at least one indoor device that are connected viaa second bus and performing communication in a master-slave method withany one of the outdoor devices being as a master device and otherdevices being as slave devices, the master device comprising: anupper-side communicator configured to be connected to the first bus, andto transmit and receive communication packets to and from theupper-level air conditioning system; an internal communicator configuredto be connected to the second bus, and to transmit and receivecommunication commands to and from each of the slave devices; anassociation information memory configured to store associationinformation obtained by associating the address in the upper-level airconditioning system allocated to each device in the lower-level airconditioning system with identification information on each device inthe lower-level air conditioning system; and a processor configured toperform a mutual conversion on the communication packets and thecommunication commands based on the association information stored inthe association information memory.